Environmental experts are warning up to a third of UK fishing waters may have to be closed to protect threatened species.

The Royal Commission on Environmental Pollution says some species risk being wiped out unless action is taken.

It echoes other studies which have called for a ban on cod fishing in the North Sea, Irish Sea and off the west coast of Scotland.

Scottish fishermen already face tough European quotas on cod fishing.

The Royal Commission says those measures, which also include restrictions on the number of days spent at sea, have failed to protect stocks.

The evidence provided by the commission's own advisers suggests that the case for such a closed area has not been made

Fisheries Minister Ross Finnie

It points out that European scientists are again calling for a total ban on cod fishing in the North Sea - something which fishermen dismiss as a political gesture.

Marine reserves established by other countries have led to a significant increase in the size and number of fish, shellfish and other animals.

Any further restriction would come as a severe blow to Scotland's fishing industry and the Scottish Executive has already signalled its opposition to closing fishing grounds.

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The European Commission is expected to call for part of the North Sea to be declared a no-go zone for cod fishing ahead of its annual round of negotiations between fisheries ministers.

A scientific report by the International Council for the Exploration of the Sea (ICES) said no cod should be caught next year in the North Sea, Irish Sea or off the west coast of Scotland because of depleted stocks.

Fisheries Minister Ross Finnie said such a move would be "an unacceptably blunt instrument not justified by the science".

"The evidence provided by the commission's own scientific advisers suggests that the case for such a closed area has not been made," Mr Finnie said.

The Scottish Fishermen's Federation (SFF) said it expected the proposals to be published on Wednesday or Thursday, ahead of the fisheries summit in Brussels.

The newly-created North Sea Regional Advisory Council (NSRAC) had opposed such a move and was proposing its own "opinion", a spokesman for the SFF said.

"This will be the RAC's own first initiative opinion and it will be important to ensure that it is taken seriously by the commission."